Considering the situation described, we have that:
a) The critical value is of z = -1.645.
b) Since the test statistic is less than the critical value, we should reject the null hypothesis H0.
<h3>What is the critical value?</h3>
We have a left-tailed test, as we are testing if the proportion is less than a value. Hence the critical value is z with a p-value equals to the significance level, hence z with a p-value of 0.05, hence z = -1.645.
<h3>What is the decision?</h3>
Considering the test statistic, for a left-tailed test, we have that:
- Less than the critical value: Reject H0.
- Equal or greater: Do not reject.
In this problem, z = -2.39 is less than -1.645, hence we should reject the null hypothesis H0.
More can be learned about the test of an hypothesis at brainly.com/question/13873630
#SPJ1
